From: Niklas Schnelle schnelle@linux.ibm.com
commit e1bff843cde62a45a287b7f9b4cd5e824e8e49e2 upstream.
Checking zdev->zbus for NULL in __zpci_event_availability() is superfluous as it can never be NULL at this point. While harmless this check causes smatch warnings because we later access zdev->zbus with only having checked zdev != NULL which is sufficient.
The reason zdev->zbus can never be NULL is since with zdev != NULL given we know the zdev came from get_zdev_by_fid() and thus the zpci_list. Now on first glance at zpci_create_device() one may assume that there is a window where the zdev is in the list without a zdev, however this window can't overlap with __zpci_event_availability() as zpci_create_device() either runs on the same kthread as part of availability events, or during the initial CLP List PCI at which point the __zpci_event_availability() is not yet called as zPCI is not yet initialized.
Reported-by: kernel test robot lkp@intel.com Reported-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Niklas Schnelle schnelle@linux.ibm.com Signed-off-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/s390/pci/pci_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/s390/pci/pci_event.c +++ b/arch/s390/pci/pci_event.c @@ -80,7 +80,7 @@ static void __zpci_event_availability(st enum zpci_state state; int ret;
- if (zdev && zdev->zbus && zdev->zbus->bus) + if (zdev && zdev->zbus->bus) pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn);
zpci_err("avail CCDF:\n");